197640019 has 2 divisors, whose sum is σ = 197640020. Its totient is φ = 197640018.

The previous prime is 197639983. The next prime is 197640041. The reversal of 197640019 is 910046791.

It is a strong prime.

It is an emirp because it is prime and its reverse (910046791) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-197640019 is a prime.

It is a super-2 number, since 2×197640019² = 78123154220640722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 197640019.

It is not a weakly prime, because it can be changed into another prime (197640059) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98820009 + 98820010.

It is an arithmetic number, because the mean of its divisors is an integer number (98820010).

Almost surely, 2^197640019 is an apocalyptic number.

197640019 is a deficient number, since it is larger than the sum of its proper divisors (1).

197640019 is an equidigital number, since it uses as much as digits as its factorization.

197640019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13608, while the sum is 37.

The square root of 197640019 is about 14058.4500923822. The cubic root of 197640019 is about 582.4942316780.

The spelling of 197640019 in words is "one hundred ninety-seven million, six hundred forty thousand, nineteen".